Field of the Invention
Embodiments of the invention generally relate to methods and apparatuses for use in suspension components. Particular embodiments of the invention relate to method and apparatus useful for equalizing ambient pressure within vehicle suspension.
Description of the Related Art
Vehicle suspension systems typically include a spring component or components and a dampening component or components. Typically, mechanical springs, like helical springs are used with some type of viscous fluid-based dampening mechanism and the two are mounted functionally in parallel. In some instances, a spring may comprise pressurized gas and features of the damper or spring are user-adjustable, such as by adjusting the air pressure in a gas spring. A damper may be constructed by placing a damping piston in a fluid-filled cylinder (e.g., liquid such as oil). As the damping piston is moved in the cylinder, fluid is compressed and passes from one side of the piston to the other side. Often, the piston includes vents there-through which may be covered by shim stacks to provide for different operational characteristics in compression or extension.
Ambient air pressure at the time of building a suspension fork is sealed inside the fork legs. When the fork is assembled at low elevation and then taken to ride at high elevations, the air pressure sealed in the lower leg, because of the decreased high elevation exterior air pressure and corresponding differential pressure, adds pressure and load to the seal, which ultimately creates significantly higher axial friction in the telescoping suspension fork.
As the foregoing illustrates, what is needed in the art are improved techniques for lowering equalizing ambient pressure within a vehicle suspension.
The drawings referred to in this description should be understood as not being drawn to scale except if specifically noted.